When being tased for police training...?

back when the handgun taser was introduced to the police force we would see a line of people holding hands and the one on the end would be tasered, the current would pass through each person and everyone would feel the constricting effect. my question now we see videos of police officers in training being shot with the taser, there are two others holding on to them to slowly and safely bring them to the ground while being tased. why is it that the current does not pass through the "taserees" skin and conduct current into the people holding him?